Dynamic imaging with multiple resolutions along phase‐encode and slice‐select dimensions

An implementation is reported of an imaging method to obtain MUltiple Resolutions along Phase‐encode and Slice‐select dimensions (MURPS), which enables dynamic imaging of focal changes using a graded, multiresolution approach. MURPS allows one to trade spatial resolution in part of the volume for improved temporal resolution in dynamic imaging applications. A unique method of Hadamard slice encoding is used, enabling the varying of the phase encode and slice resolution while maintaining a constant effective TR throughout the entire 3‐D volume. MURPS was implemented using a gradient‐recalled echo sequence, and its utility was demonstrated for MR temperature monitoring. In this preliminary work, it has been shown that changes throughout a large volume can be effectively monitored in times that would normally only permit dynamic imaging in one or a very few slices. Magn Reson Med 45:940–947, 2001. © 2001 Wiley‐Liss, Inc.